Why crash tell me please?
program My;
var
   n,k,i,i2,en,j,count:longint;
   a,b:array [1..4000] of longint;
   block:array[1..3,1..4000]of longint;
   ready:boolean;
begin
en:=1;
     for i:=1 to 3 do
     begin
          readln(n);
          for i2:=1 to n do
          begin
               read(k);
               ready:=true;
               for j:=1 to en do
               begin
                    if k=a[j] then
                    begin
                         ready:=false;
                         if block[i,j]=0 then
                         begin
                              inc(b[j]);
                              block[i,j]:=1;
                         end;
                    end;
               end;
               if ready = true then
               begin
                    a[en]:=k;
                    b[en]:=1;
                    block[i,en]:=1;
                    inc(en);
               end;
          end;
     end;

     for i:=1 to en do
     begin
          if b[i]=3 then inc(count);
     end;
     writeln(count);
end.